1. Field of the Invention
The present invention relates to a communication terminal device provided with a function that first stores and then transmits an image.
2. Description of the Related Art
Memory transmission functions are employed during transmission of a scanned image from a sending machine to a receiving machine. This memory transmission function first stores the image in a memory or the like, and then transmits that image as it is read out from the memory. This allows transmission to be performed without regard to the per-line scanning speed at which the image is scanned by the sending side. Similarly, the receiving side may employ a memory reception function that first stores the received image in a memory or the like before it is printed out. This memory reception function thus allows reception to be performed without regard to the per-line printing rate at which the image is printed by the receiving side. When both the sending side and the receiving side employ such memory transmission and reception functions during transmission, images can be transmitted very quickly.
In conventional memory transmission functions that store the image in a memory before transmitting it, dialing is performed only after all of the pages of the document to be transmitted have been stored in the memory. Thus, a great deal of time is required between the start of scanning and the start of document transmission.
In order to deal with this problem, a dialing method that dials the receiving party as soon as scanning of the document begins has been employed. This method allows transmission of the document to begin without having to wait for scanning of all the pages of the document to be completed, thus reducing the amount of time required until the start of transmission.
But since the size of the memory used to store the document image is limited, the memory may become full in the middle of scanning a page. It could happen even during scanning of the first page of the document. Normally when this happens, the transmission operation is suspended. But if this occurs while the machine is set to perform scanning and transmission simultaneously as in the above-mentioned dialing method, communication charges may be needlessly incurred without transmission of a single page of the document.
Some communication devices perform control such that document is not scanned when little space is left in the memory, but when the document is very big, or very data-intensive, such as documents that contain photographs and the like, the memory may still become full during scanning. On the other hand, when the machines are set such that they never run out of memory, small memories cannot be utilized efficiently.